"FEEDBACK" element suddenly really glitchy...

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I have written many plugins that use the Feedback element, but today it's causing cyclic glitches whenever audio passes through it... and ONLY on NEW creations...
My existing plugins are fine.

One clue is that I am using 12 of them in this particular circuit...

Has anyone got any advice?

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This morning I redid a reverb algo that had used the 12 feedback elements which been causing all the problems and it was suddenly fine... but about an hour later it was glitching again..

What is causing this?

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What's the rest of your circuit look like?

I've never tried using more than a couple of feedbacks in a circuit, I suppose using several instances could cause a problem?
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It's a simple circuit, really.. no nested feedback loops or recursive matrixes... it's simply individual delays with a feedback element in series with each and a lowpass in the feedback loop of each delay line to damp the HF response.

The outputs of the delay lines are simply summed using the "add many" element.

I have tried to remove all of the feedback elements, but even adding one back in causes stuttering.



I suspect it's a bug.

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So you're using the feedback element but not in a feedback loop?

Not sure I understand what you've got going on...
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I am using them with feedback applied, but there are no nested feedback loops or recursive matrixes.

It is a simple parallel structure of 12 delay line subcircuits.

Each delay line has it's own feedback loop and there is no additional feedback in the design.

Each of the 12 identical delay line subcircuits consist of:


input--> summer --> High cut filter--> allpass filter--> delay--> feedback--> out (this node also connects to the input summer through a multiplier).

The subcircuit has inputs for the audio signal, delay time, HC frequency, HC level, diffusion amount, and feedback level.

What I don't understand is why it works sometimes and then seems to lose synch and cause stuttering audio. When that happens, if I delete all of the feedback elements the stuttering goes away, and at that point adding even ONE will introduce stuttering....

Anyone?

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man that is weird. I'll try to reproduce it tonight and see if the same thing happens for me.

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I was wondering if this was a PPC issue, so I had a friend verify the same issue on his intel Mac... :help:

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I'm not having that problem here on either a ppc or an intel mbp.

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I get it when I have more than 4 or so feedback loops... Once it happens, then even ONE feedback loop will stutter...

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